Household ultrafiltration membrane (hollow fiber membrane) separation technology, as one of the six high-tech technologies in the 21st century, has become a standard for separation processes due to its outstanding characteristics of operation at room temperature and low pressure, no phase change, and low energy consumption. It has been widely used in developed countries and regions such as Europe and the United States. Ultrafiltration membranes have been widely used in many aspects such as drinking mineral water purification, beverages and food, medical and pharmaceuticals. Ultrafiltration membrane, ultrafiltration equipment
Household ultrafiltration is a screening process related to the size of the membrane pore size. The pressure difference between both sides of the membrane is used as the driving force, and the ultrafiltration membrane is used as the filter medium. Many small pores on the membrane surface only allow water and small molecular substances to pass through and become permeate, while substances in the original liquid whose volume is greater than the pore size of the membrane surface are trapped on the inlet side of the membrane and become concentrated liquid. To achieve the purpose of purification, separation and concentration of the original liquid.
Ultrafiltration stock solution generally refers to the solution that needs to be purified, separated or concentrated. The permeate refers to the part of the stock solution that is filtered through the ultrafiltration membrane to remove macromolecular solutes. The concentrated solution is the solution that separates the permeate from the stock solution. The remaining high concentration solution. In the water purification project, the raw liquid refers to the raw water inflow, the permeate is the purified water, and the concentrated liquid is the discharged wastewater.
A hollow fiber ultrafiltration membrane module is mainly composed of hundreds to thousands of fine hollow fiber filaments and the membrane shell. Generally, the ultrafiltration membrane with the inner diameter of the hollow fiber membrane between 0.6-6mm is called capillary ultrafiltration. Membrane, capillary ultrafiltration membrane has a large inner diameter, so it is not easy to be blocked by large particles, and it is more suitable for occasions where the concentration of the original solution is relatively high. According to different water inlet methods, hollow fiber ultrafiltration membranes are divided into two types: internal pressure and external pressure (only internal pressure is introduced)
The original liquid enters the hollow fiber first, driven by the pressure difference, penetrates the hollow fiber from the inside to the outside in the radial direction and becomes the permeate. The concentrated liquid stays in the hollow fiber and flows out from the other end. The flow direction is shown in the figure below: The function of the epoxy end seal is to seal the gap between the membrane filaments at the ends of the hollow fiber membrane filaments, thereby separating the original liquid from the permeate, preventing the original liquid from directly infiltrating into the permeate without being filtered by the membrane filaments .